The present invention generally relates to a virtual computer system and a virtual computer migration method, and in particular relates to a virtual computer system that uses a virtual server loaded with a plurality of virtual OSes (Operation Systems).
Conventionally, virtual machine technology of virtualizing server hardware and operating a virtual OS in such virtual hardware is known. In this virtual machine technology, a plurality of virtual hardware devices are prepared and a virtual server capable of simultaneously operating a plurality of virtual OSes is used. Under ordinary circumstances, since a plurality of OSes to be operated respectively in a plurality of servers can be integrated as a plurality of virtual OSes in a virtual server, server operation costs can be reduced.
In addition, with the virtual machine technology as disclosed in Japanese Patent Laid-Open Publication No. 10-283210, a live migration function of migrating a virtual OS operating in one virtual server to the other virtual server is also being developed. With the live migration function, even if one virtual server is in the middle of reading or writing data, the virtual OS can be migrated to the other virtual server.
Meanwhile, when using a storage apparatus to store data, there is a method of managing a plurality of hard disks according to a RAID (Redundant Array of Independent/Inexpensive Disks) format. Here, at least one or more logical volumes (hereinafter simply referred to as “volumes”) are formed in a physical storage area provided by a plurality of hard disks.